Science.
	The Bramble Shark (Echinorhinus brucus) is distinguished from similar-looking sharks by having two small dorsal fins located far on the back just before the tail., as well as the large, thorn-like denticles that cover its body. The Nyala (Tragelaphus angasii) is one of the most sexually dimorphic species of antelope. An adult male stands about 42 inches at the shoulder, is up to 6.5 feet long, and weighs up to 275 pounds; females are considerably smaller. Although only found in a relatvely small area of southeastern Africa, it is fairly plentiful within its range. The Gerenuk (Litocranius walleri), also known as Waller's Gazelle, is distinguished from other antelope by its long neck and long, thin legs, which allows it literally stand up to obtain tree leaves that cannot be reached by other antelope species. Hooded Seal (Cystophora cristata) This seal gets its common name from an enlargement of the nasal cavity in males that resembles a hood. That "hood" can be inflated like a balloon to become as large as the seal's head. When not inflated, the "hood" hangs down over the upper lip. Tayra (Eira barbara) This member of the weasel family grows to a length of about 30 inches, not counting a long, bushy tail that can be almost as long as the body. It is native to the neotropical deciduous and evergreen forests of Central and South America and the island of Trinidad. Arsenic (As) is a semi-metallic element that has been known since ancient times. It as been used as a poison for hundreds of years, due to its extreme toxicity to insects, bacteria and fungi. Wood Pigeon (Columba palumbus) This pigeon is generally gray in color, with a pinkish breast and ga reen, white and purple patch on the neck. The tail has a black tip, and there is a prominent white patch on each wing. The eyes are bright yellow, and the legs and bill are pink. The Brushtail Possum (Trichosurus vulpecula) is the largest possum in Australia. About the size of a domestic cat, it averages 12-24 inches in length and weighs up to 10 pounds. It has a prehensile tail that adds another 9-16 inches to overall length, a pointy snout, pink nose, and long whiskers. Fur color may be silver gray, brown, black, or gold. Insulin is a naturally-occurring hormone secreted by areas within the pancreas known as Islets of Langerhans. It is required by cells in order for them to remove and use glucose from the blood; glucose is what cells use to produce the energy necessary to performance of their functions. Bismuth (Bi) has the highest resistance to being magnetized of all metals, has a high electrical resistance, and is second only to mercury in low thermal conductivity. One bismuth compound is well known for having the ability to calm upset stomachs and stop diarrhea Narwhal (Monodon monoceros) The most characteristic feature of the narwhal is its tusk, which is always spiral in a counter-clockwise (as viewed by the animal) direction and can be as long as 9 feet. Only present in males, the tusk is actually a greatly elongated tooth. Japanese Spider Crab (Macrocheira kaempferi) The world's largest living arthropod, the Japanese Spider Crab has a leg span of up to 13 feet from claw to claw, a body up to 15 inches across, and weighs up to 44 pounds. The Whale Shark (Rhincodon typus) is the largest fish in the sea, being 18-40 feet long and weighing an average of 20.6 tons. In addition to size, the whale shark is distinguished by its blunt snout and a mouth up to 4 feet wide at the very front of the head; most other sharks have a more pointed snout and the mouth is on the underside of the head. Common Earthworm (Lumbricus terrestris), also known as the night crawler, may be up to 10 inches long. Earthworms move an incredible amount of soil as they burrow and feed. There may be as many as 3 million earthworms per acre of soil, and it has been estimated that 7½ to 18 tons of soil can be thrown up by earthworms per acre per year. Blue Wildebeest (Connechaetes taurinus) Wildebeest get their name from an Afrikaans word that means "wild beast," which is a reference to the menacing appearance presented by the animal's large head, shaggy mane, pointed beard, and sharp, curved horns.